// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/threading/worker_pool.h"

#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/location.h"
#include "base/message_loop/message_loop.h"
#include "base/run_loop.h"
#include "base/synchronization/waitable_event.h"
#include "base/test/test_timeouts.h"
#include "base/threading/thread_checker_impl.h"
#include "base/time/time.h"
#include "build/build_config.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "testing/platform_test.h"

typedef PlatformTest WorkerPoolTest;

namespace base {

namespace {

    class PostTaskAndReplyTester
        : public base::RefCountedThreadSafe<PostTaskAndReplyTester> {
    public:
        PostTaskAndReplyTester()
            : finished_(false)
            , test_event_(WaitableEvent::ResetPolicy::AUTOMATIC,
                  WaitableEvent::InitialState::NOT_SIGNALED)
        {
        }

        void RunTest()
        {
            ASSERT_TRUE(thread_checker_.CalledOnValidThread());
            WorkerPool::PostTaskAndReply(
                FROM_HERE,
                base::Bind(&PostTaskAndReplyTester::OnWorkerThread, this),
                base::Bind(&PostTaskAndReplyTester::OnOriginalThread, this),
                false);

            test_event_.Wait();
        }

        void OnWorkerThread()
        {
            // We're not on the original thread.
            EXPECT_FALSE(thread_checker_.CalledOnValidThread());

            test_event_.Signal();
        }

        void OnOriginalThread()
        {
            EXPECT_TRUE(thread_checker_.CalledOnValidThread());
            finished_ = true;
        }

        bool finished() const
        {
            return finished_;
        }

    private:
        friend class base::RefCountedThreadSafe<PostTaskAndReplyTester>;
        ~PostTaskAndReplyTester() { }

        bool finished_;
        WaitableEvent test_event_;

        // The Impl version performs its checks even in release builds.
        ThreadCheckerImpl thread_checker_;
    };

} // namespace

TEST_F(WorkerPoolTest, PostTask)
{
    WaitableEvent test_event(WaitableEvent::ResetPolicy::AUTOMATIC,
        WaitableEvent::InitialState::NOT_SIGNALED);
    WaitableEvent long_test_event(WaitableEvent::ResetPolicy::AUTOMATIC,
        WaitableEvent::InitialState::NOT_SIGNALED);

    WorkerPool::PostTask(FROM_HERE,
        base::Bind(&WaitableEvent::Signal,
            base::Unretained(&test_event)),
        false);
    WorkerPool::PostTask(FROM_HERE,
        base::Bind(&WaitableEvent::Signal,
            base::Unretained(&long_test_event)),
        true);

    test_event.Wait();
    long_test_event.Wait();
}

#if defined(OS_WIN) || defined(OS_LINUX)
// Flaky on Windows and Linux (http://crbug.com/130337)
#define MAYBE_PostTaskAndReply DISABLED_PostTaskAndReply
#else
#define MAYBE_PostTaskAndReply PostTaskAndReply
#endif

TEST_F(WorkerPoolTest, MAYBE_PostTaskAndReply)
{
    MessageLoop message_loop;
    scoped_refptr<PostTaskAndReplyTester> tester(new PostTaskAndReplyTester());
    tester->RunTest();

    const TimeDelta kMaxDuration = TestTimeouts::tiny_timeout();
    TimeTicks start = TimeTicks::Now();
    while (!tester->finished() && TimeTicks::Now() - start < kMaxDuration) {
#if defined(OS_IOS)
        // Ensure that the other thread has a chance to run even on a single-core
        // device.
        pthread_yield_np();
#endif
        RunLoop().RunUntilIdle();
    }
    EXPECT_TRUE(tester->finished());
}

} // namespace base
